Magnetite
Magnetite · Mineral Specimen and Ore Mineral
Crystal System
Cubic (Isometric), typically forming octahedral or dodecahedral crystals, also massive or granular
Mineral Group
Oxides, Spinel group
Chemical Formula
Fe3O4
Formation Process
Igneous (accessory mineral in magmatic rocks), metamorphic (regional and contact), and sedimentary (banded iron formations)
About This Crystal
Opaque, dark grey to black metallic mineral showing characteristic striations or cleavage planes on a metallic crystalline face, exhibiting a submetallic to metallic luster with fine striations
Physical Characteristics
Color: Iron-black to brownish-black; Streak: Black; Cleavage: None, exhibits octahedral parting; Fracture: Uneven to subconchoidal; Specific Gravity: 5.15 to 5.18; Tenacity: Brittle; Highly magnetic
Optical Properties
Opaque with a metallic to submetallic luster; Isotropic in reflected light
Hardness & Durability
Origin Region
Found worldwide including notable deposits in Sweden, Norway, USA (New York, Utah), Russia, and South Africa; forms in igneous, metamorphic, and sedimentary environments
Hardness & Durability
Mohs hardness of 5.5 to 6.5; moderate toughness; stable under normal conditions
Care & Maintenance
Clean with mild soap and water, dry thoroughly to prevent surface oxidation or rust, store separately to avoid scratching softer materials
Rarity & Value
Common mineral, widespread globally as an iron ore; specimens with well-formed octahedral crystals command higher collector value
Special Characteristics
Strong natural magnetism (lodestone variety exhibits permanent magnetic polarity); exhibits metallic striations on crystal faces
Lore & History
Historically known as lodestone, used in ancient times for early compass navigation; in modern metaphysical practices, it is associated with grounding, attraction of positive energy, and alignment of chakras, though these are traditional beliefs rather than scientific claims